Electric fuse.



VTo all ivhom tlcacemfi l Be itv known that AI, vLEONARD B. I"BU- CHANAN, a citizen of the UnitedStates residing at Woburn, in the county of Middlesex 'and 'State offMassachusetts, have v invented an Improvement in Electric Fuses, of

whichtlie following yis a specification,

This invention' relates to an improved in-A dicatordevlce for inclosed electric fuses of a type adapted'to show conspicuously vby .the displacement of an indicator element v1s1- .ble at the outside of the fuse, when the fuse', vis blown. out. The 'prime object 'of the invention is to provide an indicator-device of a si1nple,reliable, and effective kindthat is not attached to the fuse-wire or' str1p,fand

consequently capable of quick and convenient assemblage with the other parts in the fuse-holder. To this end I provide an indicator-member mounted so as to be visible at the outside of the fuse-shell, which is normallyheld in one position, in readiness to act, by a connectionwith a mass of material of a nature to be disintegrated by the heat incident to` a blow-out, said visible indicator-member then moving to change its position conspicuously to denote the blow-out. This mass of material to be disintegrated by the heat of the blow-out, is, in accordance with the present invention, held in a sepa-` rate compartment from the true fuse-wire but in such proximity to a high resistance shunt which is blown by the blowing of the trucfuse that the `heat therefrom will explode said mass of materialwhichfmay be guncotton or like material of a 'gas-producing lnature that isquickly'and completely disintegrated by the degree of heat evolved in the blow-out. Tl. e foregoing and other ob jects and features of the invention will be better understood from the following de tailed description taken .fin connection with the accompanying drawings.

Figure l, is a view partly in elevation and partly in lengthwise section of a fuse having any indicator-device embodying my invention.

Fig. .2, is an enlarged sectional detail of the indicator-device.

Fig. 3, is a detail elevation showing the inv dicator elements detached; and,

Fig. 4, is a transverse sectionthrough' a fuse showing a-slightly modified form and arrangement of the indicator element.

vnifncrmc FUSE.A 'y f l 1.y t.

Y Specification of Letters Patent. Patented NOV. 13, 191.7.` lf'fAppnatin'nlgiieemter 7,1914, Seriarntfzavsg.' 'Renewed Apri; 14, 191i'. serial No. 162,188.

Theinvention 'is herein, for illustrative purposes, shown'4 as embodledin a Jtype of fuse,', such `as shown' in.- Letters Patent.V

#801,467, dated October 10, 1905, it'having aptrue fuse-strip or wire'10, extended centrally lengthwise through the fuse-shell 11, and connected to the metallic end-caps 12; and ahigh resistance shunt-wire 13, extending from `end to end of the fuse connected with theend-caps thereof and lying lalong the sideof the fuse-shell.'v yThis shunt-,wire

13, should be made' .of resistance ima-f terlal, such as fine .German-silver wire, so as to carry only a trivial part of the current, and not be unduly heated until heated by the transfer of the current thereto when the fusestrip 10 has melted or vaporized. In accordance with my invention, means is provided within a 'separate compartment through which the shunt-wire passes in proximity to thev shunt-wire abovev referred to but n'ot in any way connected with or re-.

strained, thereby adapted to be exploded by the heating thereof,to release or cause a change in position of a member visible out- Side the fuse-body.` The member thus conspicuously visible'outside the fusebody is shown as a Spring-strip 1,4, fixed at one end' fuse-case and heldtherein. Washers or pads 20 of fiber or stiff textilemay be placed atA each side ofthe mass 17, to hold it confined 'in the thimble 187 and assist in preventing the, heat of the are from forcing its way through the opening in the fuse-case. -Thus it willibe noted that. the mass of combustible anddisintegrable material 17 is held in the thimble 18 in-close proximity to the additional or shunt-wire 13, and that the indicator-Strip 14 will be held down close to the shell,l in a relatively in'conspicuous position, so long as the gun-cotton is not set olf and consumed. As, soon, however, as the is set into a hole 19, therefor, through the Vfuse blows out, and the resistance shuntwire 1-3 becomes in consequence highlyheated, the mass` of gun-cotton 17 will -be instea of exten ing lengthwise of the shell, as shown in the preceding figures, is curved aroundthe shell, through some little arc, to obtain the'necessary resilient spring-out action. f I clainzy An electric-fuse comprising a casing, a fuse-Wire extended therein, and means for indicating the blowin vof said fuse consistingin a spring attac led to the outside of said casing havinga portion adapted to of the fuse to anyone in the v yvicinit In i 4 the indicator-stripla,

movevaway from said casin when released,

.a1 fastening-device for. hol ing' said `s ringl in retracted position, said fasteningevice being attache to said spring, 'and a mass of material to which said fastening-device is 'arranged in proximity to said mass of materialbut not connected with the .same or tending in any Way -to hold said s ring under restraint, the blowin of the s unt- Wire causing disintegration o the mass of material and consequent releaseof the spring, substantially as described.

In testimony whereof, I have signed my name-to this specification, in the presence of two subscribin .Witnesses LE NARD B.. BUCHANAN.

Witnesses: H v

GEORGE C. ARvEDsoN, MARY E. CARAHER. 

